Preheat your oven to 350ºF (176ºC), and lightly spray with oil a muffin tin ( or use paper liners).
In a large bowl, lightly whisk together the eggs, then mix in mashed bananas, yogurt, quark(if using), optional honey and vanilla.
In another bowl, sift together flour, cocoa, baking soda, baking powder, and salt. Mix until well combined.
Pour the wet ingredients into the dry ingredients bowl, and stir gently all together. Make sure to not over mix. Then fold in chocolate chips.
Divide the batter evenly among the muffin tin, filling each mould ¾ to almost all the way to the top.
Bake for 15-20 min or until a skewer comes out clean.
Remove from the oven, and cool in the tin for 10 mins before transferring the muffins onto a cooling rack.
Serve cool, and store remaining muffins in an airtight container for up to three days.